Field of the Invention
This invention relates to clamp assemblies for securing elongate members thereto and in particular clamping assemblies for securing long lengths of ribbon rail to a rail train.
Description of the Related Art
Modern railroad tracks are constructed using long sections of ribbon rail which presently may be up to 1600 feet in length. These sections of ribbon rail are formed by butt welding multiple sticks of rail, which traditionally come from the steel mill in thirty-nine foot or seventy-eight foot lengths. The welding of the ribbon rails is done at a welding plant and the welded ribbon rails are transported to their installation site on a specially constructed rail train. The rail train includes a plurality of rail rack cars, each typically having two racks of shelves
One car in each rail train is a tie-down car including specialized stands which include means for fixing the rails to racks on the stands to prevent longitudinal movement of the rails relative to the tie-down car. The fixing means generally includes a plurality of clamping blocks which are bolted to the stand on opposite sides of each rail so as to bear against the foot or base flange of the rail and clamp it against the stand. Typically each clamping block is held down by three or four large bolts which must be installed or removed using an impact wrench or the like. All the other racks in the train allow for relative longitudinal movement of the rails and may include rollers which support the rails. This relative movement between the racks and the rails is required in order to allow the rails to flex without stretching or compressing as the train traverses curves in the track, as well as to allow for coupler slack that exists in each of the couplers between cars. Each coupler has up to approximately 6 inches of slack. Coupler slack and thermal expansion and contraction of the ribbon rail, generally necessitates that the tie-down car be positioned near the center of the rail train so as to evenly divide the rails and to thereby insure that neither the forward end nor the rearward end of the rail can move, expand or contract a sufficient distance relative to the nearest adjacent rack that the end of the rail falls off of the rack.
In existing rail trains, worker safety is endangered by the need to manually clamp and unclamp the rails using an impact wrench or the like. A clamping mechanism that could be remotely operated would greatly improve the safety of rail loading and unloading operations.